Is utility maximization compromised by acute intoxication with THC or MDMA?

This report presents results from a within-subject, randomized, placebo-controlled experiment in which healthy participants were orally administered delta-9-tetrahydrocannabinol (THC; 10mg/70kg), the main psychoactive component of cannabis, 3,4-methylenedioxymethamphetamine (MDMA; 1.5mg/70kg), the main psychoactive component of 'ecstasy' and 'molly', and placebo across three sessions. While intoxicated, participants chose between monetary payment and social time, defined as access to their phone and pre-specified social internet sites like Facebook. The design of the experiment made possible an assessment of the acute effects of THC and MDMA on adherence to the generalized axiom of revealed preference (GARP), a necessary and sufficient condition for maximization of a well-behaved utility function. Choices made under the influence of THC, MDMA, and placebo were all GARP compliant. Thus, even when participants were acutely intoxicated with THC or MDMA, their choices remained consistent with the tenets of neoclassical choice theory.